The End of Food. Thomas F. Pawlick

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СКАЧАТЬ beginning to be understood. As late as 1975, the USDA food tables didn’t even list selenium or vitamins D and E, and they have only recently begun to include the amino acids.

      Also only partially understood are the effects each of these nutrients have on each other, or on the body when working in tandem, such as the interconnections between sodium and calcium intake noted in Chapter One. The point is that they are all important; each one affects the others, working with them or against them, in an intricate living symphony of chemical and biochemical reactions. Even the smallest excesses or deficiencies can provoke myriad unexpected results, which we ignore at our peril.

      SCURVY KNAVES

      In the 1800s, when Herman Melville wrote his classic whaling novel Moby Dick (the movie version, a century later, starred Gregory Peck), sailors would stay at sea for months, even years, and their stores of fresh vegetables would often be exhausted long before they could put into port for more provisions. Forced to subsist on diets of salt pork and biscuit, they developed a whole range of diseases stemming from dietary deficiencies, the best known of which was scurvy (“Ahoy there, you scurvy knave!”).

      The first sign of scurvy was fatigue, which kept getting worse. Then the sailor’s gums would start bleeding, followed by his skin. The blood vessels under his skin would appear to turn red and swell. If the man cut himself, the cut wouldn’t heal. His fingers and toes would swell, and his body hair would turn curly and kinky. Horny growths would appear on the skin, particularly his buttocks. He would experience increasing pain in his joints, would become pale and lethargic and unable to sleep. Next his teeth would start falling out and finally he would start to hemorrhage. Finally, thankfully, he would die.⁸

      As many as two-thirds of a ship’s crew would die this way during a long voyage. Experiments by British physician James Lind finally isolated the cause—lack of citrus or other fruits containing what was then called the “antiscorbutic factor.” Isolated nearly 200 years later, the factor was found to be a carbon compound similar to glucose, which was dubbed “ascorbic acid”—today’s vitamin C.⁹ Eventually, the British navy solved the problem by requiring all of its sailors to drink lime juice during long voyages, thus giving rise to the slang nickname for an Englishman, “limey.”

      And what has the potato lost over the past 50 years? In Canada, 57 percent of its vitamin C. The American tomato has lost 16.9 percent of its vitamin C just since 1963. And broccoli, described by reporter Picard as “a food that epitomizes the dictates of healthy eating,”¹⁰ has, according to the USDA tables, lost fully 45 percent of this crucial nutrient since John Kennedy died.

      Are Americans and Canadians likely to break out suddenly with the symptoms of advanced scurvy? Probably not in the short-term future, since other food items—including limes, lemons, and grapefruit— still contain considerable ascorbic acid. But the general trend toward drastic vitamin C loss in so many food items at the same time, a steady move away from what makes for good health and toward nutritional poverty, is hardly reassuring.

      It’s even less reassuring if one takes such scourges as heart disease or cancer into account. The causes of cancer, what John Wayne called “the big C,” and which killed him shortly after he made his last classic western, The Shootist, are in many ways still a mystery to researchers. But so-called “free radicals” are not that mysterious.

      As most of us were probably told in high school chemistry class (and promptly forgot once the exam was over), free radicals are molecules, or groups of atoms, in which one of the atoms in the group has an “unpaired” electron in its outer shell, making it unstable. Since atoms always seek stability, these molecules only exist very briefly, as intermediate products of earlier chemical reactions. As soon as they encounter another molecule with which they can combine, or from which they can scavenge an electron to pair with their extra one, they do so.

      The human body is constantly creating free radicals, most often during the process of oxidizing, or “burning” food for energy.¹¹ This process produces a type of free radical called “reactive oxygen,” which can begin a very destructive chain reaction as it attempts to bond with other atoms and achieve stability. It’s a bit like the biblical raging lion, which “goes about, seeking whom it may devour.” Snatching an electron from another atom, leaving it unstable, the oxygen radical creates “another, uglier than itself,” which will in turn attack yet other atoms, creating more free radicals, and so on, and so on.

      Raging about within our bodies, these sub-microscopic biochemical lions “may irritate or scar artery walls, which invites artery-clogging fatty deposits around the damage,” the so-called hardening of the arteries that leads to heart disease.¹² There is also “a growing body of evidence” that “many of the things we associate with getting older—memory loss, hearing impairment—can be traced to the cumulative effects of free radicals damaging DNA … thus diminishing the body’s energy supply.”¹³ Scientists have also implicated oxidative stress in the development of arthritis and cataracts.

      Worst of all, free radicals can have a “mutation-causing or mutagenic effect on human DNA, which can be a factor leading to cancer.”¹⁴ Too many free radicals, in fact, may have been what killed “the Duke,” the very symbol of cowboy courage and manly strength.

      A normal, healthy human body provided with a balanced diet has a set of natural defenses against free radicals, in the form of “anti-oxidants.” These are substances which can chemically interact with free radicals and “neutralize” them in various ways without themselves turning into radicals. Like so many microscopic Buffys stamping out vampires without becoming vampires, they de-fang the radicals, rendering them harmless.

      Foremost among these are various enzymes (proteins that help along chemical reactions without themselves being changed in the process), and the vitamins C and E. The chemical “de-fanging” activity of the enzymes depends heavily on the presence of the minerals selenium, copper, manganese, and zinc.

      And exactly what is missing or declining in the foods sold in our modern supermarkets? Vitamin C (decreased by 57 percent in Canada’s potatoes, declining fast in America’s tomatoes, broccoli, and a host of other vegetables and fruits), and copper (down across-the-board by four-fifths in vegetables in England, but unfortunately not measured in the USDA tables for 1963 or 1975). The USDA did not analyze for selenium, manganese, or zinc until recently, nor for vitamin E.

      What about vitamin A, down by 43.3 percent in red, ripe tomatoes in the U.S. since 1950, by 30.5 percent in tomato juice and 27.4 percent in tomato catsup since 1963? What is it good for?

      First, it plays a crucial role in vision, helping to maintain the clarity of the cornea of the human eye, and in the conversion of light energy into nerve impulses in the retina. Without sufficient vitamin A, people can go blind.

      In addition, vitamin A is needed to maintain what biologists call “epithelial” tissues in the body. These are the cells that form the internal and external surfaces of our bodies and their organs. They include our skin, which shields us from the outside world, and the walls that separate each of our internal organs from the others, as well as the mucus secretions that ease the movement of foods through the human digestive tract.

      What could happen if a person were to stop eating vitamin A-rich foods? The authors of Understanding Nutrition are blunt: “Deficiency symptoms would not begin to appear until after [the body’s] stores were depleted—one to two years for a healthy adult but much sooner for a growing child. Then the consequences would be profound and severe.”¹⁵

      In children, this could mean an upsurge in the negative effects of such infectious diseases as measles which, despite a vaccine available mostly in the rich countries, still kills some two million children worldwide every year. As Whitney СКАЧАТЬ